Technical Field
This disclosure relates to a sheet discriminator to discriminate sheet types, and an image forming apparatus including the sheet discriminator.
Related Art
In known image forming processes, to achieve higher printing quality, an image forming apparatus automatically discriminates sheet types and sets image forming conditions according to the detected sheet type.
An example of an image forming apparatus shows a configuration in which a sheet discriminator is disposed inside the image forming apparatus to discriminate information of a sheet being conveyed in a sheet conveying path.
This sheet discriminator includes an optical sensor that has a light emitting element and a light receiving element therein to function as a sheet information detector to detect information of a sheet. The light emitting element of the sheet information detector emits light to a surface of a sheet. Among the light emitted by the light emitting element, the light reflected on the surface of the sheet is received by a reflection light receiving element that is disposed at a position that can receive the reflected light and the light transmitted through the surface of the sheet is received by a transmission light receiving element that is received at a position that can receive the transmitted light.
Specifically, the sheet information detector causes the light emitting element to emit light to a sheet that is conveyed via a sheet conveying path and causes the reflection light receiving element to receive the light reflected on the sheet and the transmission light receiving element to receive the light transmitted through the sheet, so that the sheet information detector can detect sheet information based on optical information including a light amount of the received light.
Accordingly, based on the sheet information thus detected by the sheet information detector, a controller that functions as a sheet distinguisher to distinguish the sheet types, the image forming apparatus sets the image forming conditions according to the sheet type.
The sheet information detected by the sheet information detector includes glossiness of the sheet based on the reflected light received by the reflection light receiving element, thickness of the sheet based on the transmitted light received by the transmission light receiving element, and so forth. Based on the sheet information detected as described above, a controller that is a sheet distinguisher distinguishes a type of the sheet so as to set image forming conditions according to the respective types of the sheets.